THE CONCENTRATION OF THE SYRUP TO MASSECUITE. 



the figure at the intersection of a vertical and horizontal line gives the degree 

 Brix of the molasses in the pan, so that when the solubility of sugar becomes 

 2'0 molasses of the purity in the column selected will result. As an example 

 the solubility of sugar at the moment of observation is 3*0 and it is desired 

 to obtain molasses of 40 purity when the solubility is 2'0 ; at the intersection 

 of the line 30 and 40 is the figure 84'82, i.e., the Brix of the molasses in 

 the pan must be 84*82. 



As pointed out in dealing with the application of the brasmoscope to 

 massecuites boiled string proof, it is impossible to state beforehand what the 

 indication of the brasmoscope should be, and the brasmoscope indications must 

 be systematically compared with the actually recorded results in the factory. 

 When once the brasmoscope indications corresponding to molasses of a satis- 

 factory low purity are obtained, then it should be possible to reproduce those 

 conditions more exactly than can be done by the senses of sight and touch. 



The process of exhausting rapidly low grade massecuites mentioned above 

 as ' reversed process ' would appear to be a scheme lending itself readily 

 to a very complete control, as it would only be necessary to determine the 

 proper concentration of the low grade massecuite before taking in the sugar 

 used as ' priming,' as has already been indicated when dealing with the 

 application of the brasmoscope to massecuites boiled string proof. 



Control of the Supersaturation. As the supersaturation rises 

 so also does the elevation of the boiling point ; when once the most favourable 

 degrees of supersaturation for the different periods of the process of concentra- 

 tion in the pan have been determined, they may be referred to elevation of the 

 boiling point, and it is thus possible always to boil the pan under equal 

 conditions. For example, suppose it is desired to work with a continuous 

 feed, and it has been found that, with a boiling point elevation of 20 C. 

 the best results are obtained ; the feed and steam valves are so set that this 

 elevation is maintained as indicated by the brasmoscope reading ; should a low 

 elevation be observed it is evident that syrup is being admitted too fast, i.e., 

 the supersaturation is diminishing. Similarly the granulation and the bringing 

 up can be worked with a prearranged supersaturation as indicated and 

 controlled by the brasmoscope indication. Actually in the majority of cases 

 the skilled sugar boiler makes these observations by the senses of sight and 

 touch, and for these the brasmoscope substitutes a definite scientific relation. 



Use of the Refractometer. The methods by which the total 

 solids in sugar house products are obtained with this instrument are given in 

 Chapter XXIII. This instrument is particularly serviceable in determining in 

 a very short space of time the concentration of the massecuite in the case of 

 strikes boiled blank. The sample of material removed in the proof stick serves 

 for the determination, which can be made in two minutes. This instrument 

 gives a most valuable control over the whole process of pan boiling. 



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